A question on moving sprites

During a game loop, if the user has a key down, i want to move a sprite. Now, i've heard of several ways about dealing with the speed. Should i have the sprite only be moved after so many frames, and then when i want to increase its speed, just move it more often? Ex: move every 10th frame to every 2nd frame. Or, should i just move it more than 1 pixel at a time? This produces some jerkiness and i think would cause problems with collision detection (ie, running over the object its colliding with). thanks for any ideas,
jmiller

I'm not a skilled game programmer, but I have always moved a picture more then one pixel per time to make it go faster. Double are actually nice to work with her, because then you don't have to move 1 or 2 or 3 pixels a time, but maybe 1.5, then it looks like it walks 1.5 pixels each time, but it actually moves 1 pixel the first time, and 2 the next time and 1 the third time, and so on....

In this case, find out the time between draws, calculate a ticks-per-second structure, and work out how much you'll have to move this (otherwise on a really fast computer it will move at x pixels/s, and on a slow computer it'll move at y pixels/s, with x any y being the number of frames drawn, etc). So, you need to create an arbitrary value of movement so that you can have the code execute similarly on different spec'd machines.